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Ecosystem Services And Life Cycle Assessment Of Perennial And Annual Cropping Systems, M. Berti, A. Cecchin

IGC Proceedings (1997-2023)

Corn cultivation has negative impacts to the environment, such as nitrate leaching, soil erosion, and nitrous oxide emissions. Perennial crops such as alfalfa (Medicago sativa L.) reduce annual disturbance of soil, which affects many biogeochemical cycles that are key to provide resilience and stability to cropping systems. Four three-year crop sequences were evaluated. 1) Corn-soybean-corn (CSC); 2) alfalfa-alfalfa-alfalfa (AAA); 3) Corn-spring planted alfalfa-alfalfa (CAA); and 4) Corn-intercropped/alfalfa-alfalfa-alfalfa (CAIAA). Modeling of C and N cycles were conducted with the Denitrification-Decomposition (DNDC) model and global warming potential (GWP) was estimated using life cycle assessment (LCA) methodology. The soil organic carbon (SOC) balance …

Grass-Next – A Process-Based Model To Explore Nutrient And Carbon Dynamics In Topographically Complex Grazed Grasslands, F. Bilotto, Ronaldo Vibart, Alec D. Mackay, M. Harrison

IGC Proceedings (1997-2023)

Topographical features such as slope and aspect influence primary production, animal behavior and nutrient return to grazed grasslands. A new model was developed based on data collected during 40+ years of research in hill country landscapes, a long-term experiment on varying phosphorus (P) fertilizer rates and associated sheep stocking regimes. The Grass-NEXT model was able to simultaneously simulate total soil P (TSP), soil organic carbon (SOC) and total soil nitrogen (TSN) stock change and distribution in a topographically complex (hill country) landscape from 2003 to 2020. This model provided a basis for exploring, accounting, and reporting on changes in TSP, …

The Effect Of Legume/Grass Pasture On Soil Organic Carbon, Z. Kadziuliene, Alvyra Slepetiene

IGC Proceedings (1997-2023)

Soil organic carbon content is an important integral indicator of soil fertility. The extent at which the soil can sequestrate carbon depends on the nature of agricultural production, land use and soil type (Follet, 2001). More than two thirds of the annual grassland biomass production is allocated to below ground structures and deep humus layers are common in grassland (Körner, 2002). Grasslands differ markedly in species composition, utilisation purpose, fertilisation and this can significantly change their effect on soil organic content (Hassink & Neeteson, 1991). The objective of study was to estimate changes in the soil organic carbon content and …

Soil Respiration Measurements Reveal High Retention Of Organic Carbon From Corn Residue Derived High-Lignin Fermentation Byproduct Enabling Sustainable Lignocellulosic Biofuel Production, Michelle Sun Wang

Dartmouth College Master’s Theses

While 2G biofuel production can utilize non-edible, lignocellulosic feedstocks such as agricultural residues to produce liquid fuel, harvesting crop residues is unsustainable without careful management of the soil underneath. By harvesting a fraction of the crop residues left in the field after harvest, soil health can diminish and critically, the soil organic carbon (SOC) stored in agricultural fields can decrease. Currently, in the most popular 2G process models published, the issue of soil degradation remains unresolved with residue harvest strategies receiving considerable attention in the literature and other SOC management strategies receiving far less. Specifically, the strategy of returning the …

Long-Term Manure Application Improves Soil Health And Stabilizes Carbon In Continuous Maize Production System, Saurav Das, Daniel Liptzin, Bijesh Maharjan

Department of Agronomy and Horticulture: Faculty Publications

Soil health lies at the core of a sustainable food production system. A comprehensive evaluation of different agronomic practices and their effect on soil health is essential to determine the best practices that support soil ecosystem services. However, it may take years or decades to observe measurable changes in soil health under varying management practices. The objective of this experiment was to evaluate the effects of long-term (>77 years) manure and inorganic nitrogen (N) fertilizer on soil health and determine the interrelationship among the measured soil bio-physicochemical indicators. The study also aims to understand the sustainability of the monocropping …

Winter Wheat Cover Crop Increased Subsoil Organic Carbon In A Long-Term Cotton Cropping System In Tennessee, Rounak Patra, Debasish Saha, Sindhu Jagdamma

Biosystems Engineering and Soil Science Publications and Other Works

Long-term cover-cropping and no-tillage practices can facilitate soil organic carbon (SOC) accumulation in agroecosystems for soil health and climate mitigation benefits. However, the contribution of these conservation management practices to SOC gain from the subsoil layers is not been extensively studied. To understand this knowledge gap, it is essential to determine the distribution of total SOC and SOC fractions in response to management practices across the soil profile. Therefore, this study was conducted by leveraging a 40-year replicated field experiment in a continuous cotton (Gossypium hirsutum) system. The management treatments examined included three cover crop treatments: 1) hairy vetch, HV …

Modeling Long-Term Corn Yield Response To Nitrogen Rate And Crop Rotation, Laila A. Puntel, John E. Sawyer, Daniel Barker, Ranae N. Dietzel, Hanna Poffenbarger, Michael J. Castellano, Kenneth J. Moore, Peter Thorburn, Sotirios Archontoulis

John E. Sawyer

Improved prediction of optimal N fertilizer rates for corn (Zea mays L.) can reduce N losses and increase profits. We tested the ability of the Agricultural Production Systems sIMulator (APSIM) to simulate corn and soybean (Glycine max L.) yields, the economic optimum N rate (EONR) using a 16-year field-experiment dataset from central Iowa, USA that included two crop sequences (continuous corn and soybean-corn) and five N fertilizer rates (0, 67, 134, 201, and 268 kg N ha-1) applied to corn. Our objectives were to: (a) quantify model prediction accuracy before and after calibration, and report calibration steps; (b) compare crop …

Modeling Long-Term Corn Yield Response To Nitrogen Rate And Crop Rotation, Laila A. Puntel, John E. Sawyer, Daniel W. Barker, Ranae Dietzel, Hanna Poffenbarger, Michael J. Castellano, Kenneth J. Moore, Peter J. Thorburn, Sotirios V. Archontoulis

Department of Agronomy and Horticulture: Faculty Publications

Improved prediction of optimal N fertilizer rates for corn (Zea mays L.) can reduce N losses and increase profits. We tested the ability of the Agricultural Production Systems sIMulator (APSIM) to simulate corn and soybean (Glycine max L.) yields, the economic optimum N rate (EONR) using a 16-year field-experiment dataset from central Iowa, USA that included two crop sequences (continuous corn and soybean-corn) and five N fertilizer rates (0, 67, 134, 201, and 268 kg N ha^-1) applied to corn. Our objectives were to: (a) quantify model prediction accuracy before and after calibration, and report calibration steps; (b) …

Using A Vnir Spectral Library To Model Soil Carbon And Total Nitrogen Content, Nuwan K. Wijewardane

Department of Biological Systems Engineering: Dissertations and Theses

n-situ soil sensor systems based on visible and near infrared spectroscopy is not yet been effectively used due to inadequate studies to utilize legacy spectral libraries under the field conditions. The performance of such systems is significantly affected by spectral discrepancies created by sample intactness and library differences. In this study, four objectives were devised to obtain directives to address these issues. The first objective was to calibrate and evaluate VNIR models statistically and computationally (i.e. computing resource requirement), using four modeling techniques namely: Partial least squares regression (PLS), Artificial neural networks (ANN), Random forests (RF) and Support vector regression …

Root Biomass And Soil Carbon Response To Growing Perennial Grasses For Bioenergy, Leonard C. Kibet, Humberto Blanco-Canqui, Robert B. Mitchell, Walter H. Schacht

Department of Agronomy and Horticulture: Faculty Publications

Background: Dedicated bioenergy crops such as switchgrass (Panicum virgatum L.), miscanthus [Miscanthus x giganteus (Mxg)], indiangrass [Sorghastrum nutans (L.) Nash], and big bluestem (Andropogon gerardii Vitman) can provide cellulosic feedstock for biofuel production while maintaining or improving soil and environmental quality. To better understand bioenergy crop effects on soils, we studied changes in soil properties of a Tomek silt loam under inorganic fertilization of switchgrass after 4 years and warm-season grass monocultures and mixtures after 6 years in eastern Nebraska.

Methods: The first experiment had two study factors: two switchgrass harvest dates (August and …

Influence Of Corn Stover Harvest On Soil Quality Assessments At Multiple Locations Across The U.S., Diane E. Stott, Virginia L. Jin, Thomas F. Ducey, Douglas L. Karlen, Gary E. Varvel, Jane M. F. Johnson, John M. Baker, Shannon L. Osborne, Jeff M. Novak, Paul R. Adler, Greg W. Roth, Stuart J. Birrell

Douglas L Karlen

Corn (Zea mays L.) stover has been identified as a biofuel feedstock due to its abundance and a perception that the residues are unused trash material. However, corn stover and other plant residues play a role in maintaining soil quality (health) and enhancing productivity, thus use of this abundant material as feedstock must be balanced with the need to protect the vital soil resource. Plant residues provide physical protection against erosion by wind and water, contribute to soil structure, nutrient cycling, and help sustain the soil microbiota. Replicated plots were established on productive soils at several locations (IA, IN, MN, …

Dryland Soil Carbon Dynamics Under Alfalfa And Durum-Forage Cropping Sequences, Upendra M. Sainju, Andrew W. Lenssen

Andrew W. Lenssen

Forages grown in rotation with or without cereals to sustain dryland soil water content and crop production may influence C dynamics. We evaluated the effect of alfalfa (Medicago sativa L.) and durum (Triticum turgidum L.)-annual forage cropping sequences on above- (stems + leaves) and belowground (roots) biomass C inputs and dryland soil organic C (SOC), particulate total C (PTC), microbial biomass C (MBC), and potential C mineralization (PCM) at the 0–120 cm depth. Cropping sequences were continuous alfalfa (CA), durum-barley (Hordeum vulgare L.) hay (D-B), durum-foxtail millet (Setaria italica L.) hay (D-M), durum-Austrian winter pea (Pisum sativum L.)/barley mixture hay …

Field-Scale Soil Property Changes Under Switchgrass Managed For Bioenergy, Marty R. Schmer, M. A. Liebig, K. P. Vogel, Robert B. Mitchell

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

The capacity of perennial grasses to affect change in soil properties is well documented but information on switchgrass (Panicum virgatum L.) managed for bioenergy is limited. An on-farm study (10 fields) in North Dakota, South Dakota, and Nebraska was sampled before switchgrass establishment and after 5 years to determine changes in soil bulk density (SBD), pH, soil phosphorus (P), and equivalent mass soil organic carbon (SOC). Changes in SBD were largely constrained to near-surface depths (0–0.05 m). SBD increased (0–0.05 m) at the Nebraska locations (mean=0.16 Mgm^-3), while most South Dakota and North Dakota locations showed declines …

Soil Carbon Dynamics During A Long-Term Incubation Study Involving 13C And 14C Measurements, Ronald F. Follett, Eldor A. Paul, Elizabeth G. Pruessner

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Soil organic matter is the earth's largest terrestrial reservoir of carbon (C). Thus, it serves as a major control on atmospheric carbon dioxide (CO₂) levels. To better understand these controls, decreases in soil organic C (SOC), soil microbial biomass (SMB) C, and the role of SMB as a source of mineralizable C were measured during a long-term incubation (853 days) without added substrate. The 2 soils used were a Weld loam (fine montmorillonitic, mesic, Aridic Paleustoll) from near Akron, Colorado, and a Duroc loam (fine silty, mixed mesic Pachic Haplustoll) from near Sidney, Nebraska. The Akron soil was …